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  • Accepted Manuscript: Single-stride exposure to pulse torque assistance provided by a robotic exoskeleton at the hip and knee joints
Title: Single-stride exposure to pulse torque assistance provided by a robotic exoskeleton at the hip and knee joints
Robot assisted gait retraining is an increasingly common method for supporting restoration of walking function after neurological injury. Gait speed, an indicator of walking function, is correlated with propulsive force, a measure modulated by the posture of the trailing limb at push-off. With the ultimate goal of improving efficacy of robot assisted gait retraining, we sought to directly target gait propulsion, by exposing subjects to pulses of joint torque applied at the hip and knee joints to modulate push-off posture. In this work, we utilized a robotic exoskeleton to apply pulses of torque to the hip and knee joints, during individual strides, of 16 healthy control subjects, and quantified the effects of this intervention on hip extension and propulsive impulse during and after application of these pulses. We observed significant effects in the outcome measures primarily at the stride of pulse application and generally no after effects in the following strides. Specifically, when pulses were applied at late stance, we observed a significant increase in propulsive impulse when knee and/or hip flexion pulses were applied and a significant increase in hip extension angle when hip extension torque pulses were applied. When pulses were applied at early stance, we observed a more » significant increase in propulsive impulse associated with hip extension torque. « less
Authors:
;
Award ID(s):
1638007
Publication Date:
NSF-PAR ID:
10109286
Journal Name:
2019 IEEE 16th International Conference on Rehabilitation Robotics (ICORR)
Page Range or eLocation-ID:
874 to 879
Sponsoring Org:
National Science Foundation
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    The type of FRT device will affect ground-reaction forces (GRFs) during and after the training. Specifically, the uni- and bidirectional braces will increase GRFs when compared with the elastic band.

     Study Design:

    Crossover study.

     Level of Evidence:

    Level 2.

     Methods:

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    FRT after ACL reconstruction can acutely alter gait kinetics during training. Devices can be applied to selectively alter gait kinetics. However, the long-term effects of FRT after ACL reconstruction with these devices are still unknown.

     Clinical Relevance:

    FRT may be applied to alter gait kinetics of the involved limb after ACL reconstruction, depending on the device used.

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    Abstract

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